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ffmpeg.wasm-core
Commit d9d9fd94 authored by Michael Niedermayer's avatar Michael Niedermayer
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avcodec/error_resilience: Optimize motion recovery code by using blcok lists 

This makes the code 7 times faster with the testcase from libfuzzer
and should reduce the amount of timeouts we hit in automated fuzzing.
(for example 438/fuzz-2-ffmpeg_VIDEO_AV_CODEC_ID_RV40_fuzzer)

The code is also faster with more realistic input though the difference
is small here as that is far from the worst cases the fuzzers pick out

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpegSigned-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
parent f1214ad5
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Showing with 83 additions and 34 deletions
libavcodec/error_resilience.c
View file @ d9d9fd94
......@@ -373,23 +373,39 @@ static void v_block_filter(ERContext *s, uint8_t *dst, int w, int h,
}
}
#define MV_FROZEN 8
#define MV_CHANGED 4
#define MV_UNCHANGED 2
#define MV_LISTED 1
static av_always_inline void add_blocklist(int (*blocklist)[2], int *blocklist_length, uint8_t *fixed, int mb_x, int mb_y, int mb_xy)
{
if (fixed[mb_xy])
return;
fixed[mb_xy] = MV_LISTED;
blocklist[ *blocklist_length ][0] = mb_x;
blocklist[(*blocklist_length)++][1] = mb_y;
}
static void guess_mv(ERContext *s)
{
uint8_t *fixed = s->er_temp_buffer;
#define MV_FROZEN 4
#define MV_CHANGED 2
#define MV_UNCHANGED 1
int (*blocklist)[2], (*next_blocklist)[2];
uint8_t *fixed;
const int mb_stride = s->mb_stride;
const int mb_width = s->mb_width;
int mb_height = s->mb_height;
int i, depth, num_avail;
int mb_x, mb_y, mot_step, mot_stride;
int blocklist_length, next_blocklist_length;
if (s->last_pic.f && s->last_pic.f->data[0])
mb_height = FFMIN(mb_height, (s->last_pic.f->height+15)>>4);
if (s->next_pic.f && s->next_pic.f->data[0])
mb_height = FFMIN(mb_height, (s->next_pic.f->height+15)>>4);
blocklist = s->er_temp_buffer;
next_blocklist = (s->er_temp_buffer + 2 * sizeof(int) * s->mb_stride * s->mb_height);
fixed = s->er_temp_buffer + 4 * sizeof(int) * s->mb_stride * s->mb_height;
set_mv_strides(s, &mot_step, &mot_stride);
num_avail = 0;
......@@ -439,8 +455,22 @@ static void guess_mv(ERContext *s)
return;
}
blocklist_length = 0;
for (mb_y = 0; mb_y < mb_height; mb_y++) {
for (mb_x = 0; mb_x < mb_width; mb_x++) {
const int mb_xy = mb_x + mb_y * mb_stride;
if (fixed[mb_xy] == MV_FROZEN) {
if (mb_x) add_blocklist(blocklist, &blocklist_length, fixed, mb_x - 1, mb_y, mb_xy - 1);
if (mb_y) add_blocklist(blocklist, &blocklist_length, fixed, mb_x, mb_y - 1, mb_xy - mb_stride);
if (mb_x+1 < mb_width) add_blocklist(blocklist, &blocklist_length, fixed, mb_x + 1, mb_y, mb_xy + 1);
if (mb_y+1 < mb_height) add_blocklist(blocklist, &blocklist_length, fixed, mb_x, mb_y + 1, mb_xy + mb_stride);
}
}
}
for (depth = 0; ; depth++) {
int changed, pass, none_left;
int blocklist_index;
none_left = 1;
changed = 1;
......@@ -449,20 +479,24 @@ static void guess_mv(ERContext *s)
int score_sum = 0;
changed = 0;
for (mb_y = 0; mb_y < mb_height; mb_y++) {
for (mb_x = (mb_y ^ pass) & 1; mb_x < s->mb_width; mb_x+=2) {
const int mb_xy = mb_x + mb_y * s->mb_stride;
int mv_predictor[8][2];
int ref[8];
int pred_count;
int j;
int best_score;
int best_pred;
int mot_index;
int prev_x, prev_y, prev_ref;
if (fixed[mb_xy] == MV_FROZEN)
continue;
for (blocklist_index = 0; blocklist_index < blocklist_length; blocklist_index++) {
const int mb_x = blocklist[blocklist_index][0];
const int mb_y = blocklist[blocklist_index][1];
const int mb_xy = mb_x + mb_y * mb_stride;
int mv_predictor[8][2];
int ref[8];
int pred_count;
int j;
int best_score;
int best_pred;
int mot_index;
int prev_x, prev_y, prev_ref;
if ((mb_x ^ mb_y ^ pass) & 1)
continue;
av_assert2(fixed[mb_xy] != MV_FROZEN);
av_assert1(!IS_INTRA(s->cur_pic.mb_type[mb_xy]));
av_assert1(s->last_pic.f && s->last_pic.f->data[0]);
......@@ -476,8 +510,7 @@ static void guess_mv(ERContext *s)
if (mb_y + 1 < mb_height)
j |= fixed[mb_xy + mb_stride];
if (!(j & MV_FROZEN))
continue;
av_assert2(j & MV_FROZEN);
if (!(j & MV_CHANGED) && pass > 1)
continue;
......@@ -486,7 +519,7 @@ static void guess_mv(ERContext *s)
pred_count = 0;
mot_index = (mb_x + mb_y * mot_stride) * mot_step;
if (mb_x > 0 && fixed[mb_xy - 1]) {
if (mb_x > 0 && fixed[mb_xy - 1] > 1) {
mv_predictor[pred_count][0] =
s->cur_pic.motion_val[0][mot_index - mot_step][0];
mv_predictor[pred_count][1] =
......@@ -495,7 +528,7 @@ static void guess_mv(ERContext *s)
s->cur_pic.ref_index[0][4 * (mb_xy - 1)];
pred_count++;
}
if (mb_x + 1 < mb_width && fixed[mb_xy + 1]) {
if (mb_x + 1 < mb_width && fixed[mb_xy + 1] > 1) {
mv_predictor[pred_count][0] =
s->cur_pic.motion_val[0][mot_index + mot_step][0];
mv_predictor[pred_count][1] =
......@@ -504,7 +537,7 @@ static void guess_mv(ERContext *s)
s->cur_pic.ref_index[0][4 * (mb_xy + 1)];
pred_count++;
}
if (mb_y > 0 && fixed[mb_xy - mb_stride]) {
if (mb_y > 0 && fixed[mb_xy - mb_stride] > 1) {
mv_predictor[pred_count][0] =
s->cur_pic.motion_val[0][mot_index - mot_stride * mot_step][0];
mv_predictor[pred_count][1] =
......@@ -513,7 +546,7 @@ static void guess_mv(ERContext *s)
s->cur_pic.ref_index[0][4 * (mb_xy - s->mb_stride)];
pred_count++;
}
if (mb_y + 1<mb_height && fixed[mb_xy + mb_stride]) {
if (mb_y + 1<mb_height && fixed[mb_xy + mb_stride] > 1) {
mv_predictor[pred_count][0] =
s->cur_pic.motion_val[0][mot_index + mot_stride * mot_step][0];
mv_predictor[pred_count][1] =
......@@ -606,24 +639,24 @@ skip_mean_and_median:
s->decode_mb(s->opaque, ref[j], MV_DIR_FORWARD,
MV_TYPE_16X16, &s->mv, mb_x, mb_y, 0, 0);
if (mb_x > 0 && fixed[mb_xy - 1]) {
if (mb_x > 0 && fixed[mb_xy - 1] > 1) {
int k;
for (k = 0; k < 16; k++)
score += FFABS(src[k * linesize[0] - 1] -
src[k * linesize[0]]);
}
if (mb_x + 1 < mb_width && fixed[mb_xy + 1]) {
if (mb_x + 1 < mb_width && fixed[mb_xy + 1] > 1) {
int k;
for (k = 0; k < 16; k++)
score += FFABS(src[k * linesize[0] + 15] -
src[k * linesize[0] + 16]);
}
if (mb_y > 0 && fixed[mb_xy - mb_stride]) {
if (mb_y > 0 && fixed[mb_xy - mb_stride] > 1) {
int k;
for (k = 0; k < 16; k++)
score += FFABS(src[k - linesize[0]] - src[k]);
}
if (mb_y + 1 < mb_height && fixed[mb_xy + mb_stride]) {
if (mb_y + 1 < mb_height && fixed[mb_xy + mb_stride] > 1) {
int k;
for (k = 0; k < 16; k++)
score += FFABS(src[k + linesize[0] * 15] -
......@@ -654,18 +687,34 @@ skip_mean_and_median:
changed++;
} else
fixed[mb_xy] = MV_UNCHANGED;
}
}
}
if (none_left)
return;
for (i = 0; i < mb_width * mb_height; i++) {
int mb_xy = s->mb_index2xy[i];
if (fixed[mb_xy])
next_blocklist_length = 0;
for (blocklist_index = 0; blocklist_index < blocklist_length; blocklist_index++) {
const int mb_x = blocklist[blocklist_index][0];
const int mb_y = blocklist[blocklist_index][1];
const int mb_xy = mb_x + mb_y * mb_stride;
if (fixed[mb_xy] & (MV_CHANGED|MV_UNCHANGED|MV_FROZEN)) {
fixed[mb_xy] = MV_FROZEN;
if (mb_x > 0)
add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x - 1, mb_y, mb_xy - 1);
if (mb_y > 0)
add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x, mb_y - 1, mb_xy - mb_stride);
if (mb_x + 1 < mb_width)
add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x + 1, mb_y, mb_xy + 1);
if (mb_y + 1 < mb_height)
add_blocklist(next_blocklist, &next_blocklist_length, fixed, mb_x, mb_y + 1, mb_xy + mb_stride);
}
}
av_assert0(next_blocklist_length <= mb_height * mb_width);
FFSWAP(int , blocklist_length, next_blocklist_length);
FFSWAP(void*, blocklist, next_blocklist);
}
}
......
libavcodec/h264dec.c
View file @ d9d9fd94
......@@ -285,7 +285,7 @@ int ff_h264_slice_context_init(H264Context *h, H264SliceContext *sl)
mb_array_size * sizeof(uint8_t), fail);
FF_ALLOC_OR_GOTO(h->avctx, er->er_temp_buffer,
h->mb_height * h->mb_stride, fail);
h->mb_height * h->mb_stride * (4*sizeof(int) + 1), fail);
FF_ALLOCZ_OR_GOTO(h->avctx, sl->dc_val_base,
yc_size * sizeof(int16_t), fail);
......
libavcodec/mpeg_er.c
View file @ d9d9fd94
......@@ -109,7 +109,7 @@ int ff_mpeg_er_init(MpegEncContext *s)
er->mb_stride = s->mb_stride;
er->b8_stride = s->b8_stride;
er->er_temp_buffer = av_malloc(s->mb_height * s->mb_stride);
er->er_temp_buffer = av_malloc(s->mb_height * s->mb_stride * (4*sizeof(int) + 1));
er->error_status_table = av_mallocz(mb_array_size);
if (!er->er_temp_buffer || !er->error_status_table)
goto fail;
......
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